Mite infestation in Hedgehogs (Erinaceidae) in Israel – Characterization and Response to Treatment Horowitz, I.,1* Krupnik, S.,2 Bourdeau, P.,3 Landau, U.,4 Anglister, N.,1 Alias, R.1 and Zur, G.4 1 Zoological Center Ramat Gan (Safari) & Israeli Wildlife Hospital, 1 HaZvi Ave., Ramat Gan, P.O. Box 984, Israel. 2 Veterinary Clinic, 14 Rimon Str., Gealya, Israel. 3 Veterinary school - Oniris – Atlanpole 44307 , Nantes, France. 4 Koret School of Veterianry Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot, 76100, Israel. * Corresponding author: Dr. Igal Horowitz DVM Dipl. ECZM (Wildlife Population Health), Zoological Center Ramat Gan (Safari) & Israeli Wildlife Hospital, 1 HaZvi Ave., Ramat Gan, P.O. Box 984. Israel. Tel: +972-3-6305318, Mobile: +972- 0544-650000, Fax: 00972-6305303. Email: [email protected]. ABSTRACT Hedgehogs (Fam. Erinaceidae) are among the most common mammals in Israel. Their innate sensitivity to external and internal parasites can cause critical damage to their population that could create an imbalance of the ecological environment. Mite are common external parasites of hedgehogs and the current recommended treatment is the use of ivermectin. The hypothesis of this study was that hedgehogs are infested with mites in their normal state and in disease, however with a difference in the severity of infection depending on the hedgehogs' general health condition. The purposes of this study were (a) Investigation and characterization of mites infesting healthy hedgehogs captured in their natural habitat; (b) Characterize the disease caused by mites in clinically affected hedgehogs submitted to a wildlife hospital (IWH) and (c) to assess the success of treatment with ivermectin. Data were collected over a period of one year ( July 2011-July 2012) and included skin scrapings, microscopic examinations and fixation of mites for morphologic identification of mites' species. A disease severity scale was devised by the combination of clinical signs and microscopic examination of mites. Seventy hedgehogs were captured in their natural habitat, out of which 65 were not infested with mites and 5 were infested. Mite species were identified as Sarcoptes scabiei, Caparinia tripilis and one mite of the family Laelaptiae. Ninety three hedgehogs were brought to the Israeli wildlife hospital (IWH), out of which 48 were infested with mites identified as Sarcoptes scabiei. Thirty-four of the infested hedgehogs had dermatological signs only, suggesting that mange was not associated with any other internal diseases or injuries. No differences were found in the survival time of hedgehogs for the different degrees of skin disease, but survival rates dropped significantly during the first ten days of hospitalization, regardless of the severity of the dermatological disease. The release of hedgehogs back into the wild was made possible after 80-130 days of hospitalization, when their clinical signs had resolved. The significance of this work was the identification of the mite Sarcoptes scabiei as the most common mite species infesting hedgehogs in Israel and emphasizing that this species is a zoonotic parasite. Furthermore, to the best knowledge of the authors, this is the first report to describe the presence of a mite from the Laelaptidae family in a hedgehog in Israel. The clinical importance of this study is in realizing that prognosis is not related to the severity of the dermatological disease. The critical days for survival are in the first 10 days of hospitalization. Keywords: Hedgehog; Erinaceus concolor; Hemiechinus auritus; Mites; Sarcoptes scabiei; Notoedres cati; Caparinia tripilis; Laelapidae; Mange. Israel Journal of Veterinary Medicine Vol. 75 (1) March 2020 Mite Infestation in Hedgehogs (Erinaceidae) in Israel 17 Research Articles INTRODUCTION Table 1: Scoring system for mites infestation and skin problems Hedgehogs (Erinaceidae) are common mammals in Africa, 0 No mites, no clinical signs Asia and Europe (1). Mites are common external parasites 1 Mites in the absence of clinical sings of hedgehogs (2). Hedgehogs are very sensitive to external 2 Mites and appearance of alopecia and/ or itching 3 Mites and itching and/or crusts and internal parasites and this may lead to a decline in their 4 Mites and generalized skins lesions, crusts and itching population and cause an imbalance of the ecological systems (3). The mites that affect hedgehogs most commonly are: cording their data, which included estimated age, sex, weight, Caparinia tripilis, Sarcoptes scabiei, Notoedres cati (4, 5, 6). length, and after collecting skin samples, which consisted of Mite infestation primarily cause dermatological signs. skin scrapings from 3 regions from every hedgehog: ears, The clinical signs of mange are pruritus, lignification and nose and feet. crusts. The crusts are hard and thick and first visible in Data from affected hedgehogs that were brought to the areas such as the head, face and legs (7, 8, 9). In severe IWH between July 2011 and July 2012 were collected. All cases, dermatological changes extend to the rest of the animals were examined for their general health condition body and cause breakage of the spines from their roots and skin lesions. A scoring system for sick individuals was with resultant spine loss and as a result affected hedgehogs developed at the IWH (Table 1) and the affected hedgehogs often fail to roll up resulting in a loss of their protective were scored accordingly. The intensity of the infestation as ability, hypothermia and behavioral changes (9, 10). In well as the response to treatment was recorded. Skin scrapes were taken from all affected body sites. addition, the affected skin is often secondarily infected All skin samples underwent microscopic fixation and with bacteria (7). examination for mites and for their further identification. The current specific recommended treatment of hedge- The fixation was performed with Hoyer's medium (Dr. Yuval hogs for mites is Ivermectin (11). According to data from Gottlib Laboratory, Israel). the Israeli Wildlife Hospital (IWH), from 2010 there Treatment success with Ivermectin (Ivomec®, Merial, has been significant increase in the number of mange- Brazil) at a dose of 0.2-0.4 mg/kg body weight, per os (PO) affected hedgehogs that were brought to the hospital for or subcutaneously (SC) every 14 days for 3-5 treatments (8) treatment (Unpublished data, Personal communication: was assessed weekly and based on the clinical evaluation of Y. Horowitz). the hedgehogs and the detection of mites on microscopic There is a dearth of studies dealing with external parasites examination. Any animal dying during the course of treat- of hedgehogs and especially regarding their prevalence in the ment was recorded in relation to the severity of its disease wild population in Israel. This study planned to: (a) Examine condition. The treatment period until full recovery was the prevalence of mites on healthy hedgehogs captured in generally between 6 weeks to 3 months. their natural habitat and (b) characterize of the disease Statistical methods used to analyze data derived were caused by mites in clinically affected hedgehogs submitted Kaplan-Meier estimator and the Pearson’s test. Analysis was to a wildlife hospital (IWH) and (c) assess the efficacy of carried out using JMP 7 software (SAS Co.). Ivermectin for treatment. Mortality in the graph presented (Graph 1), is repre- sented by a decrease in the percentage of surviving hedgehogs MATERIALS AND METHODS relative to day zero. The recovery was set to the time when Two groups of hedgehogs were included in the study: wild the hedgehogs were released back into the wild. Length of hedgehogs that were captured in open areas in their natural time to release was conditioned on the absence of mites on habitat and sick wild hedgehogs that were transported to the skin scrapings and regrowth of spines and hair coat. In order IWH by individuals who found them. to properly present the effect of the treatment, only hedge- The first group of animals was captured between May hogs without related diseases were included. and September 2011, during the night. All captured animals All aspects of the study were approved by the Ethics were returned to their habitat after physical examination, re- Committee of the Hebrew University of Jerusalem, Approval 18 Horowitz, I. Israel Journal of Veterinary Medicine Vol. 75 (1) March 2020 Research Articles Table 2: Data from the captured hedgehogs from the wild In order to estimate the effectiveness and the Males Females impact of Ivermectin treatment, the survival rate Species Total Young Mature Young Mature of hedgehogs in those animals, which were not Hemiechinus auritus 2 10 4 9 26 (37%) experiencing any concomitant disease, was exam- Erinacceus concolor 6 8 7 23 44* (63%) ined. The effect of the treatment with Ivermectin 8 (11.5%) 18 (26%) 11 (16.5%) 32 (46%) 70 was assessed by survival rate of hedgehogs that * p<0.05 (Pearson’s test) dermatologically were only affected with mange. No significant difference in the hedgehogs' No. MD-11-12901-2, and the Israeli Nature and Parks survival was found for the different disease severity degrees. Authority, approval No. 2011/38156. Over all, 19 of 34 hedgehogs survived (55.8%) (Graph 1). No significant difference in the hedgehogs' survival was RESULTS found for the different disease severity degrees; however, it was found that survival rates were low especially in the Seventy hedgehogs were caught in their natural habitats. first ten days, possibly as a result of stress caused from the Most of the hedgehogs (n=44) belonged to the species capture. Erinaceus concolor (63%) and 26 (37%) were of the species Hemiechinus auritus (Table 2). Sixty five individuals were free of mites and five were infested, and only one had skin lesions. DISCUSSION Sixty-six mites were harvested from the five hedgehogs These results indicate that only a small number of wild caught in their natural habitats.